257171708641 has 9 divisors (see below), whose sum is σ = 259794915289. Its totient is φ = 254574742000.

The previous prime is 257171708623. The next prime is 257171708657. The reversal of 257171708641 is 146807171752.

The square root of 257171708641 is 507121.

It is a perfect power (a square), and thus also a powerful number.

257171708641 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 195647867041 + 61523841600 = 442321^2 + 248040^2 .

It is not a de Polignac number, because 257171708641 - 2¹⁹ = 257171184353 is a prime.

It is a super-2 number, since 2×257171708641² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (257171708041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 51216711 + ... + 51221731.

Almost surely, 2^257171708641 is an apocalyptic number.

257171708641 is the 507121-st square number.

257171708641 is the 253561-st centered octagonal number.

It is an amenable number.

257171708641 is a deficient number, since it is larger than the sum of its proper divisors (2623206648).

257171708641 is an frugal number, since it uses more digits than its factorization.

257171708641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10244 (or 5122 counting only the distinct ones).

The product of its (nonzero) digits is 658560, while the sum is 49.

Multiplying 257171708641 by its sum of digits (49), we get a square (12601413723409 = 3549847²).

The spelling of 257171708641 in words is "two hundred fifty-seven billion, one hundred seventy-one million, seven hundred eight thousand, six hundred forty-one".